A novel partial male sterility resource in bread wheat

A plant of the wheat cultivar Moulin grown in a greenhouse was found to be completely sterile. The study of the F1 and F2 offspring of the plant pollinated by Moulin showed that in field conditions the sterility was partial (fertility reduced by 91.6% with only a few completely sterile plants), recessive and monogenic. The F1 crosses of the mutant Moulin with Ms1b/ms1b Sirocco and Probus monosomic 4B showed that the gene for sterility is not located in chromosome 4B and hence cannot be allelic to the recessive allele ms1b which confers complete male sterility in wheat. The expression of sterility was demonstrated in wheat backgrounds with high levels of fertility. This is the first time partial-monogenic sterility is reported in wheat. This kind of sterility is of no interest for producing wheat F1 hybrids. However, it might be of interest for recurrent selection, or dynamic management of genetic resources where limited intermating is required, as well as in the study of genes involved in microsporogenesis.